Field pole and rotor construction



Nov. 23 1926.

1,608,314 0. 'r. HIBBARD FIELD POLE AND ROTOR CONSTRUCTION Filed Oct. 2, 1922 E? V l I INVENTOR C/MRLEJ Tfiumw f/LBB/IBD VMf /WW v ITTORN'EYJ Patented Nov. 23, 1926.

UNITED STATES V l,6fi8,3 14

PATENT 'FFEEM onannns TRUMAN nrnnann, on MINNEAPOLIS, MINNESOTA, r sers-non rontno'raro MACHINERY MANUFACTURING COMPANY, OF MINNEAPOLIS, MINNESOTA, A COR- PORATION OF MINNESOTA.

FIELD POLE AND ROTOR CONSTR'LICTION. M

Application filed Gctober 2, 1922. Serial No. 591,852.

This invention relates to new and useful improvements in the construction of revolve as the well known two-four-or six-pole piece types, often require very heavy field pole pieces in their rotor construction to produce the electrical results deslred. These pole pieces are usually built up of laminated magnetic sheet metal securely riveted together, each pole thus forming a unit in itself before being assembled in the rotor. In machines of this type and particularly in the four-pole piece type, difiiculty is pften experienced in designing a safe and suitable means for anchoring the pole pieces to the rotor shaft, due to the enormous centrifugal force resulting from the rapidly revolving pole pieces upon the shaft. It is also difficult to anchor the pole pieces to the rotor shaft without weakening the shaft and with retention of sufficientcross'section for the magnetic flux from the pole to pole. At present the above difficulty 1s overcome In various ways: For example, there is pro; vided a shaft-forging having an enlarged integral central portion upon which thepole pieces are rigidly mounted by such means as dovetailing, etc., which necessarily incurs considerable expense due to the cost of such forging and the amount of mechanical labor required to prepare same for assembling; or, another exampleis the construction of the four poles in a single piece with a centralhole into which a shaft is passed. In this latter case, the field coils must be wound on each pole after assembly. This is tedious and expensive. Coils have also been separately wound and thereafter slipped upon the poles, but for high speed such coils are not saIe.

In this novel invention, means are provided wherebythe poles-pieces, after they have bccnwound in the usual way, may be readily and quickly assembledor joined together to form a complete rotor independmalring a self-contained rigid unit of the this novel device. shown such a pole-punching or lamination ent of the shaft on which they are to be I mounted. The coil is retained at both ends ment of this improved construction, the centrifugal force resulting from the revolution of the pole pieces will be equally distributed and a magnetic path is also provided which pa'th'is additional to and independent of the shaft. 7

The specific object of this invention, therefore, is to provide an improved field pole piece and rotor-construction.

Other objects of the invention will more fully appear from the following detailed description and the accompanying drawings, and will be pointed out in the annexed claims.

In the accompanying drawings there has been disclosed a structure adapted to carry out the objects of the invention, but it is to be understood that the invention is not con fined to the exact features shown, and various changes may be made within the scope of the claims which follow.

In the drawings:

Figure 1 is a view in cross-section of an assembled rotor and showing the means pro- 7 each other to form a complete rotor, some of the windings being omitted;

Figure 2 is a perspective view of an assembled field pole, member Without the winding; and t Figure 3 is a plan vievi of one of the sheet-metal punchings or laminations used in the construction of a pole member.

In the selected embodiment of the invention here shown there is illustrated anassemble'd rotor, such as is commonly used in the construction of electric motors and generators. This rotor comprises the usual field poles 4 on which the field coils 5 are wound." These pole pieces or members and coils are rigidly mounted upon the usual shaft 6. While these novel pole members maybe integrally formed and provided with the novel interlocking device, they are preferably formed of a plurality of members of magnetic sheet material each such member or lamination being formed with In Figure 3, there is adapted for use in the construction of these novel field pole pieces or members. "It has a body 7 and pole tips8. An arcuately formed surface 9, corresponding to the curvature of the shaft 6 on which it is to be vided forinterloclring the pole pieces with Figure 3.

mounted, is, provicled'at one'end of the pole body, as shown in Figure 1. A recess or notch ll is also preferably provided at this curved: end of the pole punching and its function is to provide a suitable keyway adapted to receive key 13 when the rotor is assembled and mounted upon the shaft. A novel rectangular lug 14' is preferably providedon one side of the pole body 7 and is integrally formed therewith, as shown in I An aperture 15 is provided in the lug 14k and is adapted to receive a suitable rivet orpin 16 when the rotor is assem bled as shown in Figure 1. The apertures l7 are provided in the pole'body 7 to receive the rivets l8. I

In assembling this novel field pole member, the pole punchings or laminations are stacked in groups upon the rivets 18, upon anyvsujitabletable or bench, each succeeding I group being placed upon the preceding one in reversed relation until the desired pole length has been attained.v Thus the lugs 14L of each group are alternately oppositely disposed so that the groups are in spaced relation in order to receive the similargroups otthe adjacent pole pieces or membersin interlapping or interposed relation. The ends of the rivets 18 are then headed over so; that the pole punchings are securely riveted. together and the assembled pole piece is completed as shown in Figure 2. The field coils 5 are then wound upon the pole pieces, thereby con'ipleting the field poles preparatory to being assembled in the or.

The pole pun'chings may be grouped in any quantity desired to produce the most suitable size interlocking lugs, but it is to ie understood that said punchings are prefcrably uniforn'ily'grouped and stacked, in allofthe field pole pieces or members required for a given motor or generator, soas to assure that the "lugs will perfectly interlocltwith each other when the field pole piecesare asseii ibled in the rotor, as shown in Figure 1. As soon as the field polepie ces have been fitted together the pins 16 are inserted in the alined apertures 15, thussecurely interlocking the pole pieces with each other.. These rivets or pinsmay be headed over or not as desired, as they cannot work loose jvhen the rotor is revolving due tothe centrifugal action of the field poles acting thereon. a ,H

Bythe use of this improved,,CQnstruction the iitirerdtor I11ly. ,b completely assembled witl 'it theusual shafn and l so in inudllssti 'ethan isordinarily requi ed h 'the pr carna e has. lieei sewn, a, t r,

m ste mi imum, There yre f. r w:

umuted to this particular type of titer-11316 as sent c nstructiom thus reducing v the above described construction may be adapted to a two pole machine equally as well and also to machines having a greater number of poles, such as six, eight or ten pole machines. I I

I claim as my invention:

1 A rotor comprising a plurality of field pole members, each member having lugs projecting therefromand positioned to permit a coil to be wound about the body of the member and have the lugs of one pole member interlap with the lugs of an, adjacent pole ni eii'iberavl1e11 in assembled relation, means securing: together the interlapping lugs of adjacent pole members, and a shaft whereon the pole members are mounted. Y c

A rotorcompris'irig a plurality o f field pole nien'ibers, each formed with" groups of lugs projecting'from opposide sides and positioned to'permit a coil t'ofbe wound about the body of the member and have the groups of one pole rneinber interlap'with corresoonding lug groups of, an adjacent pole member, vmeans passing through the interlappinglngs of adjacent members to secure the members together, and a shaft Whereon the pole members are mounted.

3. A rotor comprising a central shaft, a lurality, of field pole members secured on said shaft, each field pole member having a plurality of lugs spaced apart projecting outwardly therefrom upon opposite sides, the lug-s of one pole member passing between the corresponding lugs of the adjacent pole member, and means passing through the lugs so interl a ppe'd for rigidly securing them together. 7 v v j j Y 'A rotor comprising acentral' shaft, a plurality of field pole members seated on said shaft and secured thereon, each field pole member having a plurality of lugs ,spaced a 'qart projecting outwardly there trom upon opposite sides, the lugs of'one pole member passing between the corresponding lugs ofthe adjacent pole member, said lugshaving holes therein and means passing through the interlapping lugs of adjacent pole members and securing them and said pole members together.

5, A field pole member comprising an elongated body portion adapted to have a wound thereabout, one end of said porgj ii having opposed projections, the other end thereof being terminally concave to fit *o or aft a d alue p i ti s f d hotly iiicrtionadjacent saidconcave end whereby the members of aceiit pole meini a ro rgmey be ei dckeda n hc, n a es the at t .to afiel cit th r ng pr sedv t ei rr- .lie uiiilerst od thiat the lnventi n t" ictions", the other end thereof being termmtn' concave to lit a' rotor shaft, and

0 ment and a lug projecting from each lamination adjacent its base, the lugs of one group of laminations being disposed on the opposite side of the pole member from those of the adjacent group of laminations and positioned to have the lugs of one member to interlock with corresponding lugs of the adjacent pole member.

In Witness whereof, I have hereunto setmy hand this 27th day of September, 1922.

CHARLES TRUMAN I-IIBBARD. 

